Tape reel latch



F. B- FROEHLICH TAPE REEL LATCH Oct. 11, 1966 3 Sheets-Sheet 1 Filed Dec. 23, 1963 lN-VENTOR FREDERICK B. FROEHLICH ATTORNEY 1966 F. B. FROEHLICH 3, 7

TAPE REEL LATCH Filed Dec. 25, 19 63 5 Sheets-Sheet 2 FIG.3

Oct. 11, 1966 F U H 3,278,133

TAPE REEL LATCH Filed Dec. 23, 1963 5 Sheets-Sheet 5 FIG.4

United States Patent 3,278,133 TAPE REEL LATCH Frederick E. Froehlich, Hyde Park, N.Y., asslgnor to International Business Machines Corporation, New York, N.Y., a corporation of New York- Filed Dec. 23, 1963, Ser. No. 332,754 7 (Ilairns. (Cl. 242-683) This invention relates in general to novel means for attaching a reel to a drive shaft and more particularly to an expanding arbor and cam lever form of latching device for quickly removing and assembling a reel of magnetic tape in tape reading and writing machines.

Heretofore, a considerable amount of time and careful effort were required by a machine operator each time tape reels were to be removed and other reels secured to the drive and rewind shafts. Various forms of screw fasteners and expanding rubber arbors were used in the art, and they presented difficulties in that screw assembly with light pressure meant a loose reel, and a tightly fastened screw by a strong operator meant stripped threads. However screwed fast, the reel assembly operation was always time consuming because of the number of hand turns required to unscrew or forwardly rotate the large knobs on the outer ends of the assembly screws. Now, by means of the devices of the present invention, a great saving in time is effected because a quick light flip of a cam lever serves to open or close the frictional latch means for the reel. Not only is time saved, but the mode of operation is improved because the same sure tight reel securing operation is secured by the quick easy swing of the cam lever, independent of the degree of strength of the machine operator.

An object of the invention is to provide an improved tape reel latch device which is quickly, easily and surely effective.

Another object of the invention is to provide an all metal form of expanding arbor for holding a tape reel on a drive shaft without exerting undue pressure within a plastic reel.

Another object of the invention is to provide a cam lever so mounted and associated with an expanding arbor as to make it uniquely suited for quickly releasing and fastening tape reels.

Another feature of the invention is to so proportion a reel release straddle cam handle or lever and its housing cover that the lever is of wide rounded proportions and recessed but exposed along one wide outer edge so that a plurality of fingers can grasp the lever edge and easily flip it open, and the palm heel of a hand can strike the lever surface to easily swing it closed and flush with a flat outer housing cover surface.

Another object of the invention is the provision of safety devices to prevent an expanding arbor from overenlargement and fracture if rotated without being confined. The expanding element of the arbor is a split ring or mandrel which is manually confined within the hub of a tape reel; however, should the arbor be rotated without an assembled reel, there is danger in the over expansion of the split ring and its being cast off in fractions. In the present instance, novel precautionary measures are taken by notching an outer annular ring around the periphery of the split ring and fitting into said ring notch a strong continuous band or ring which, although it permits limited expansion of the split ring for reel securing purposes, prevents over expansion by embracing the split ring when it is slightly overenlarged.

A further object of the invention is to provide an expanding arbor cover which serves for a variety of purposes in an unusual way. The cover in addition to its usual protective function and decorative appearance, is

Ice

formed with a large open sided recess or finger tip hollow to receive the operating cam lever and furnish an operating environment for the lever, said cover also being shiftable and formed with a tapered edge to cam the split ring as a compressive wedge and expand the ring as a binding mandrel. The open side of the cover recess provides access for several finger tips to engage the cam lever edge and easily flip the lever for arbor disengagement, and the flat side of the cover provides a reference surface which when matched by the flat side of the cam lever as pushed by the heel of a hand, indicates that the arbor and reel are fully latched.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of the preferred embodiment of the invention, as illustrated by the accompanying drawings.

In the drawings:

FIG. 1 is an exploded perspective view showing the parts of the tape reel latch.

FIG. 2 is a side elevation view showing the main parts in a tape reel engaging position.

FIG. 3 is a sectional elevation view taken along line 33 in FIG. 2 and through the center of the latch when the cam lever is closed to expand the arbor and fasten the tape reel onto the driving means.

FIG. 4 is a sectional elevation view also taken through the center of the reel latch as 33 but showing some parts in full and showing the cam lever open and the arbor collapsed to loosen the tape reel for removal.

FIG. 2 shows the parts in general with the expanding arbor or tape reel latch 12 revealed in a side elevation illustration. The view shows the main parts comprising the tape reel 11, which is to be secured to the drive shaft 14 by the expanding arbor 12 as operated by opened and closed positions of wide cam lever 13, shown closed in FIG. 2.

The interior construction of the arbor is shown in the lower exploded perspective view of FIG. 1. Shaft 14 has fastened on it circular shouldered drum 15 with central hub 16 and having a tapped central opening 17. Assembled over drum 15 and against the drum flange is inner hoop or split ring 18 which has tapered outer edge 19. This cooperates with related opposed taper 20 formed on one inner edge of outwardly expanding split mandrel 21. Mandrel 21 is formed also with a second inner tapered face 22 cooperating with taper edge 23 on shiftable cover ring 24. Rings 18 and 24 operate as compressive wedges which, when forced together, expand mandrel 21 within a tape reel hub to latch it on. Safety ring 10 is a continuous metal band which fits loosely in a circumferential notch 9 in mandrel 21 without interfering with its normal expansion and contraction. However, ring 10 does prevent mandrel 21 from overexpanding and fracturing should arbor 12 be operated without the confining presence of tape reel 11.

Shiftable cover 24 is formed with central opening 26 and shoulder 25 for receiving hardened washer 28 against which are pressed a series of spring cup washers 29 and.

outer cam ring 30. Assembly screw 31 passes through all washers and rings and is threaded securely in tapped hole 17 in shaft 14 within hub 16 of the drum on the drive shaft. Screw 31 is formed with cylindrical shank 32 over which slide ring 30 and washers 29. Also formed on screw 31 is a flat pivot extension 33 to which is pivotally secured the wide straddle cam lever 13 by pin 36 centered in screw end 33 and fastened to it. Lever 13 is formed with two cam flats 34 and 35 on its hub which cooperate with the outer face of ring 30. One fiat 35 forces ring 30, washers 28 and 29, and cover 24 inwardly to expand arbor 12, FIG. 3, and hold a reel on it. The other flat 34, at a 60 angle to flat 35, is at a lower level and allows washers 29 to spring outwardly to collapse the arbor, FIG. 4 and free the reel for removal. Shims 38 provide for fine regulation of pressure between 28 and 35.

Cover 24 is shaped with cavity 27 which not only houses lever 13, as shown in the upper right drawing, but it also provides room for a plurality of finger tips to pass behind the top edge of level 13 in opening 39 and rapidly flip it open. Lever 13 swings outwardly approximately 60, allowing cover 24 to move outwardly as urged by washers 29 and the split rings. This frees the mounted tape reel for removal.

In order to grip a mounted tape reel, lever 13 is pushed inwardly with the palm heel of one hand. During the first part of such cam lever movement the axial play between cover 24 and the split rings is eliminated. The second part of the lever movement expands the arbor until it matches the inner diameter of the mounted tape reel. The third and final part of the lever movement compresses washers 29 to apply a uniform axial load. This is against the expanded arbor as flat 35 rests against ring 30 with the lever 13 flush with the face of cover 24, FIG. 3, when locked closed. Due to the mechanical advantage of lever 13, the required force to latch and unlatch the reel is small and is applied rapidly.

A pin 40, FIG. 3, is shown as the means for securing the drum 15 to the drive shaft 14 so that the frictionally wedged parts against a reel hub 41 serve to connect the reel for rotation as shaft 14 rotates in the bearing block 42 fastened to frame 43. Flange 8 of drum 15 is wide enough to hold rings 18 and 21 and the edge of cover cam 23 as shown. Ring 18 is a frictional wedge for connecting the inner and outer parts.

Reel hub 41 is at times a metallic casting with a finely finished inner surface, and in other constructions, the entire reel frame 11 is of plastic including the hub. In any event, excessive pressures inside the hub are to be avoided to prevent distortion of the reel and its flanges which are to remain parallel and avoid binding or misaligning the reeled film or tape 44 thereon.

FIG. 4 shows that a great saving in time of operation is effected because a quick light outward flip of the straddle cam lever 13 by one or more fingers, rocks the lever outward and its cam face 35 moves outward and the cover 24 is disengaged by the axial spring thrust to relieve the inward pressure normally exerted by the Belleville Washers 29; there ring 21 contracts, and reel 11 may be slipped outward over cover 24. A time of operation of about three seconds here contrasts with several times that figure for use of prior art latches. When operated in reverse, after a reel 11 is assembled, FIG. 4, pressure of fingers or the heel of the palm against extending lever 13, swings it easily and firmly back closed, FIG. 3, so that when the surfaces 45 and 46 are matched coplanar and cam face 35 is flat against washer 30, the arbor is fully expanded to latch the reel 11 in place ready for rotation by shaft 14. The resultant uniform force on the inner diameter of the mounted tape reel ranges from about 210 to 350 pounds. Due to mechanical advantage of the straddle cam handle 13, the required force to latch and unlatch the reel is in the range of only 9-15 pounds, depending on the size of the inner diameter of the tape reel hub.

Ring or band although of small cross section is of great strength and formed as a continuous ring of steel or other material of good tensile qualities. Provision of ring 10 on the split expanding grip ring 21, alleviates a safety hazard which could be encountered during high speed tape rewind without a mounted tape reel to confine ring 21. By reason of the present precautionary means, the split ring 21 cannot overexpand and break because it can expand only as far as the inner diameter of the endless steel band 10. Sufficient clearance is provided between the groove 9 and the ring 10 to allow the expanding ring 21 to grip varying inner diameters of tape 4 reel hubs finished within reasonable high and low limits of tolerance.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. A reel securing device with a tapped drive shaft and an expanding arbor device thereon, comprising a shouldered circular flange drum fastened to said shaft, an inner tapered split ring and an outer tapered cam ring on said drum, an expanding mandrel on said drum between said rings and formed with inwardly tapered ends which are engaged by said rings for expansion, a fulcrum screw fastened in said shaft tap, spring means on said screw and pressing against said outer cam ring, and a tightening lever pivoted on said screw with a cam face pressing against said spring means, whereby said lever may release the spring means to free a reel or apply pressure against said spring means to force said cam ring against said mandrel to wedge the mandrel to an expanding size tightly within a reel.

2. A reel securing device according to claim 1 wherein said lever is formed with a flat operating arm and said outer cam ring is a thick cover casing formed with a large recess in which said lever is recessed with said operating arm norm-ally flush with the outer face of said cover, said arm being wide enough to be operated by either a plurality of fingers or the palm heel of a hand when flipped outward to release a reel or pushed flush to engage a reel.

3. A reel securing device according to claim 1 wherein said fulcrum screw is formed with a smooth shank, and said spring means comprises a plurality of spring cup washers loosely assembled on said shank.

4. A securing device for detachably mounting a magnetic tape reel on a drive shaft comprising a circular shouldered drum having a central hub fastened to said shaft, an inner split ring assembled on said drum and formed with a tapered outer edge, an outwardly expanding split mandrel also assembled on said drum and formed with a taper opposing the taper of said inner ring, said mandrel being formed with another outer taper, -a shiftable cover ring formed with a taper edge cooperating with said outer taper of the mandrel, said inner ring and cover ring operating as compressive wedges which together expand the mandrel wtihin a tape reel hub to latch it to said drum and shaft, said shiftable cover being formed with a central opening and a shoulder for receiving a series of spring cup washers and an outer cam ring, a central screw passing through all washers and cam ring and threaded into a central tap in the end of said drive shaft within said drum, said screw being formed with a cylindrical shank over which the cup washers and cam ring slide, said screw being formed also with a fiat pivot extension, a wide straddle cam lever pivotally mounted on said screw extension, said cam lever being formed with two cam flats on its hub which cooperate with the outer face of the cam ring, one cam flat serves to force the ring washers and cover inwardly to expand the mandrel, and the other cam fiat is at a lower lever and allows the cup washers to spring outwardly to free said cover, collapse the mandrel and free the reel for removal.

5. A securing device of the kind set forth in claim 4 and wherein said cover is formed with a cavity which houses said lever and also provides room for a plurality of finger tips to pass behind the top edge of the lever to rapidly flip it open.

6. A reel latching device for detachably mounting a reel on a driving means comprising, an expanding arbor on said driving means, said arbor including a split ring, a continuous safety ring encircling said arbor to prevent it from over expanding, said split ring being formed with a circumferential groove wherein said safety ring fits loose- 1y to allow normal expansion and contraction of said split ring but prevent overexpansion thereof whereby fracture of the split ring is prevented, said split ring being formed also with at least one inner tapered cam face, and arbor operating means including a circular cam with a tapered cam edge cooperating with said ring cam face to expand the ring, said operating means having resilient spring means for pressing against said circular cam, and a lever for applying pressure by said spring means to force said cam to expand said split ring for operating said arbor to expand it to latch a reel to said driving means.

7. A latching device according to claim 6 wherein said operating means includes a flanged drum for supporting said expanding arbor, and a friction ring placed between said drum and arbor for connecting the drum and the arbor when the latter is expanded.

References Cited by the Examiner UNITED STATES PATENTS 771,902 10/1904 Frank 24272.1 791,759 6/1905 Eddy 24284.8 842,862 2/1907 Crane 24272.1 1,485,290 2/ 1924 Philhower 24272.1

OTHER REFERENCES IBM Technical Disclosure Bulletin (1) Tape Reel Securing Means, vol. 4, N0. 3, August 1961, pages 10, 11.

IBM Technical Disclosure Bulletin (2) Quick Mount And Remove Tape Reel Late vol. 6, No. 4, September 1963, pages 83, 84.

FRANK J. COHEN, Primary Examiner.

MERVIN STEIN, STANLEY N. GILREATH, W. S.

BURDEN, Assistant Examiners. 

1. A REEL SECURING DEVICE WITH A TAPPED DRIVE SHAFT AND AN EXPANDING ARBOR DEVICE THEREON, COMPRISING A SHOULDERED CIRCULAR FLANGE DRUM FASTENED TO SAID SHAFT, AN INNER TAPERED SPLIT RING AND AN OUTER TAPERED CAM RING ON SAID DRUM, AN EXPANDING MANDREL ON SAID DRUM BETWEEN SAID RINGS AND FORMED WITH INWARDLY TAPERED ENDS WHICH AR E ENGAGED BY SAID RINGS FOR EXPANSION, A FULCRUM SCREW FASTENED IN SAID SHAFT TAP, SPRING MEANS ON SAID SCREW AND PRESSING AGAINST SAID OUTER CAM RING, AND A TIGHTENING LEVER PIVOTED ON SAID SCREW WITH A CAM FACE PRESSING AGAINST SAID SPRING MEANS, WHEREBY SAID LEVER MAY RELEASE SAID SPRING MEANS TO FORCE SAID CAM RING AGAINST AND MANDREL TO WEDGE THE MANDREL TO AN EXPANDING SIZE TIGHTLY WITHIN A REEL. 